Dip tank for toxic fluids



Uafi. 8 1963 Filed Dec. 20, 1960 T MT Nu m W M NH T 0% T & fiwn 0 E ..L

Y B O m z z 2 m. l 4 M 0 l 4 6 4 3 6 .i, 4 M 0 4A 3 3,MZ,M Patented Jan.8, 1963 hce 3,072,64ii DH TANK FGR TUXIC FLUKDS Leon G. Tripiett,Rosamond, Calif, assignor to the United States of America as representedby the Secretary of the Air Force Filed Dec. id, 1950, Ser. No. 77,254

2 Claims. (Cl. 98115) (Granted under Title 35, US. Code (1952), sec.266) The invention described herein may be manufactured and used by orfor the United States Government for governmental purposes withoutpayment to me of any royalty thereon.

This invention relates to a. device for removal of gases from tankswhere toxic fluids are used for cleaning or other uses and, moreparticularly, to a device for removing fumes from a tank wherein toxicliquids are used for degreasing and cleaning of machine parts and likearticles.

As is well known, the problem of safety to workers around tanks andother apparatus where toxic fluids are used is an acute problem.Apparatus now in use for this purpose is elaborate and costly. Vacuumapparatus requires electric motors, force feed systems and elaborate andcostly ducting.

The object of the present invention is the provision of a closed cabinetfor holding volatile toxic cleaning fluid, for example, degreasingapparatus for machine parts by hand dipping.

A further object of the invention is the provision of a device whereinmaximum safety for personnel, maximum efficiency and ease of operation,and minimum cost are achieved.

A further object of the invention is the provision of a device wherein asource of compressed air, for example, a shop air line is used forcreating a vacuum for removing of fumes.

A further object of the invention is the provision of a cleaning unitraised to a convenient working height where visibility is provided.

In the drawing, PEG. 1 is a perspective view of the device.

FIG. 2 is a detail with portions broken away, of the vent duct from thetank and its connection with the shop air line.

FIG. 3 is a side view of the cabinet with portions broken away showingthe device installed.

FIG. 4 is a fragmentary view of a portion of the frame and tank with thetop and sides removed.

Referring more in detail to the drawing, a cabinet frame is indicatedgenerally by the numeral It comprises angle iron legs 12 braced bysuitable brace element 14. An open topped main tank 16 of materialsuitable for containing toxic cleaning fluids is welded or otherwisesuitably attached to the inner facing surfaces of the angle iron 12 andplaced at an expedient working height.

A door 18 located on the front of the cabinet is hinged by means of ahorizontal hinge 20 substantially at the level of the top of the tankIt; for convenient access and for placement of material to be cleaned.The upper wall or top cover portion of the cabinet is placed at anangle, for example, an angle depressed 65 from the horizontal, and ismade of transparent ncncorrodable material, preferably reinforced glass,so that there is complete visibility of the contents of the tank andcomplete protection of the operator from toxic fumes rising therefrom.The cover or top portion may be permanently secured or be removable, asdesired.

A tray or inner receiving tank 24 is positioned within the tank 16 andis provided with a perforated floor 26, which is raised and spaced fromthe bottom of the tank 16 by means of legs 28. The legs 28 may bepermanently attached by welding or other suitable means or the tray 24may be removable as desired. The floor of the tank 16 is provided with acentral drain opening 32, and an attached drain pipe 34 and controllingvalve 36. The tank material may be made of any suitable material whichis impervious to the toxic liquid to be contained therein. The jointsand seams are made airtight. Shielding wall sections are attached tosides, back and front as shown at 40, 41 and 42.

A vertical flue or vent pipe 44 has a horizontal section, which isbrought through the rear Wall of the tank, and an elbow 46 bent at anapproximate angle so that it presents an open mouth 48 a few inchesabove the level of liquid in the tank. A pipe 50 is connected to theshop air line (not shown) and led through a control valve 52, through asuitable fitting 5d and into the vent pipe 44 at a point slightly belowthe level of the mouth 48, and upwardly a distance, for example 30inches into the vent pipe 44. Aluminum tubing because of its lightweightand noncorrosive quality have been successfully used for this purpose.Aspirator action thus augments the upward draft in the flue 44, causingsuction and consequent vacuum in the cabinet space above the work tank,and the removal of fumes therefrom.

It will now be apparent that the device offers a maximum of safety tothe worker. The toxic fumes are drawn off efliciently and vented withoutthe necessity of complicated and expensive installations.

While the invention is shown and described in connection with one formfor illustrative, rather than restrictive purposes, it is obvious thatchanges and modifications may be made by those skilled in the artwithout departing from the scope and spirit of the invention as definedin the accompanying claims.

I claim:

1. A safety cabinet for degreasing articles where toxic fluid isemployed as a cleaning agent, said cabinet comprising a back wall, afront wall, side walls and a top wall, a frame for supporting saidwalls, said top wall comprising non-corrosive transparent material andformed to slope downwardly from rear to front, a main tank locatedwithin said cabinet and supported by said frame in such manner as toprovide a closed space within said cabinet above said tank, ahorizontally hinged door on said front wall for insertion and removal ofarticles to be cleaned, a floor in said main tank, said floor beingprovided with an outlet opening, means providing a closable drainsecured in said opening, a receiving tray positioned within said maintank, a perforated floor in said tray spaced from the floor of said maintank, an aspirator tube entering said cabinet through a rear wallthereof, said tube being provided with a mouth opening directeddownwardly and located above said main tank to receive fumes emanatingfrom said tank, a vertical section on said aspirator tube locatedrearwardly and outside of said tank, a pipe connected to an air pressuresource, said pipe entering said tube at a point outside said main tank,said pipe extending upwardly within said tube a distance equaling aportion only of the height thereof thereby providing aspirator actionfor withdrawing toxic fumes from said main tank upwardly through saidtube.

2. A safety cabinet for degreasing articles where toxic fluid isemployed as a cleaning agent, said cabinet comprising a frame, an opentopped tank having a base and side walls, said tank being secured tosaid frame, said base being provided with a drain orifice, valve meansconnected with said orifice for controlling fluid flow therethrough, aperforated tray smaller than and having the same configuration as saidtank, means secured to said tray for mounting said tray within andspaced from said tank, a series of side walls secured to said frameextending above and encompassing said tank, an inclined top secured tosaid side walls to produce an enclosed space above said tank, ahorizontally hinged door located in one of said encompassing side wallsabove the level of said tank for insertion and removal of articles to bedegreased, an aspirator tube through another of said encompassing sidewalls above said tank, a downwardly directed portion at the end of saidtube within said enclosure to receive fumes emanating from said tank, avertical section on said aspirator tube located rearwardly and outsideof said safety cabinet, a pipe connected to an air pressure source, saidpipe entering said vertical section at a point outside said cabinet, andextending upwardly within said section a distance equaling a portiononly of the height thereof thereby providing aspirator action forWithdrawing toxic fumes from the enclosed space above said main tankupwardly through said tube.

References Cited in the file of this patent UNITED STATES PATENTS GreatBritain Nov. 21,

1. A SAFETY CABINET FOR DEGREASING ARTICLES WHERE TOXIC FLUID IS EMPLOYED AS A CLEANING AGENT, SAID CABINET COMPRISING A BACK WALL, A FRONT WALL, SIDE WALLS AND A TOP WALL, A FRAME FOR SUPPORTING SAID WALLS, SAID TOP WALL COMPRISING NON-CORROSIVE TRANSPARENT MATERIAL AND FORMED TO SLOPE DOWNWARDLY FROM REAR TO FRONT, A MAIN TANK LOCATED WITHIN SAID CABINET AND SUPPORTED BY SAID FRAME IN SUCH MANNER AS TO PROVIDE A CLOSED SPACE WITHIN SAID CABINET ABOVE SAID TANK, A HORIZONTALLY HINGED DOOR ON SAID FRONT WALL FOR INSERTION AND REMOVAL OF ARTICLES TO BE CLEANED, A FLOOR IN SAID MAIN TANK, SAID FLOOR BEING PROVIDED WITH AN OUTLET OPENING, MEANS PROVIDING A CLOSABLE DRAIN SECURED IN SAID OPENING, A RECEIVING TRAY POSITIONED WITHIN SAID MAIN TANK, A PERFORATED FLOOR IN SAID TRAY SPACED FROM THE FLOOR OF SAID MAIN TANK, AN ASPIRATOR TUBE ENTERING SAID CABINET THROUGH A REAR WALL THEREOF, SAID TUBE BEING PROVIDED WITH A MOUTH OPENING DIRECTED DOWNWARDLY AND LOCATED ABOVE SAID MAIN TANK TO RECEIVE FUMES EMANATING FROM SAID TANK, A VERTICAL SECTION ON SAID ASPIRATOR TUBE LOCATED REARWARDLY AND OUTSIDE OF SAID TANK, A PIPE CONNECTED TO AN AIR PRESSURE SOURCE, SAID PIPE ENTERING SAID TUBE AT A POINT OUTSIDE SAID MAIN TANK, SAID PIPE EXTENDING UPWARDLY WITHIN SAID TUBE A DISTANCE EQUALING A PORTION ONLY OF THE HEIGHT THEREOF THEREBY PROVIDING ASPIRATOR ACTION FOR WITHDRAWING TOXIC FUMES FROM SAID MAIN TANK UPWARDLY THROUGH SAID TUBE. 